I always thought it odd that a team like ElementaryOS with a clearly defined "ethical code and goal" would choose Medium, which is an anti-consumer and anti-privacy company (e.g. try accessing Medium on a mobile phone with a smaller screen).
That is explained in the very first paragraph of the article (emphasis mine):
"In 2016, elementary moved to a Medium publication to host our official blog. At the time, Medium was touted as a simple, clean, and reader-focused host for writers. They supported custom domains, a robust API, RSS, rich formatting, and great image embedding. We had been largely happy with the experience—as were our readers—but something changed in 2017."
Yes -- good on them changing, and bravo to them for calling it out and saying why. In my opinion they put a lot of effort into making this post, and it shows.
Good on them for changing.